An SC light source, which is one example of a wideband light source, is an important light source that is expected to be applied to a variety of fields of application from the standpoint of the high output characteristic, wide range characteristic, and spectrum flatness. Although a variety of constitutions have been proposed as such SC light source apparatus, a constitution that generates SC light within an optic fiber is generally widely used on account of being straightforward and allowing an increase in the interaction length and because spectrum control is also straightforward.
Further, a coherent wideband light source disclosed in Patent Document 1 and a wideband infrared pulse laser light source disclosed in Non-Patent Document 1 for example, are known as an SC light source apparatus of this kind.    Patent Document 1: Japanese Patent Application Laid-Open No. H11-160744    Non-Patent Document 1: Okuno and five others, “Wideband near infrared pulse laser light source that uses nonlinearity of optical fiber”, Proceedings of the Twenty-first Near Infrared Forum, the Near infrared Society, November 2005, page 173